JPH01169295A - Heat exchanger - Google Patents

Abstract

PURPOSE:To improve the heat exchanging efficiency and miniaturize the title device by arranging small diameter pipes in a grid pattern and displacing the arrangement of the small diameter pipes in adjacent pipe groups by a half pitch. CONSTITUTION:Small diameter pipes 31 are all arranged in the A-A direction, and small diameter pipes 34 are all arranged in the B-B direction. Pipe groups so arranged are stacked in layers to form a grid pattern. Relative to the positioning of a pipe group 31A, a pipe group 31B is so positioned that its small diameter pipes 31 may be positioned nearly middle of the pitch L1 of the small diameter pipes 31 of 31A. The same is true with the pipe groups 34A and 34B. Therefore, the fluid flow contacts successively 31C 34B 31B 34 A 31A, and changes its course in a complex manner to contact all the small diameter pipes circumferentially and axially. Since the fluid stays longer in contact with the small diameter pipes as it flows at a constant speed, the heat exchanging efficiency can be significantly improve, and, because functional parts that perform the heat exchange are built in a compact form by the small pipe groups, miniaturization becomes feasible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat exchanger constructed from thin tubes that can improve heat exchange efficiency without adding fins to the heat exchanger tubes.

[Conventional technology]

Usually, in a heat exchanger that exchanges heat between a heating fluid and a heated fluid, in order to improve the heat exchange efficiency,
It is common practice to provide a large number of heat transfer fins on a large number of heat transfer tubes forming a heat receiving section or a heat radiating section.

As such conventional heat exchangers with heat transfer fins, for example, there is a proposal (Japanese Unexamined Patent Publication No. 147995/1983) which improves plate-like fins as shown in FIG. 8, and a proposal as shown in FIG. Proposal for improving net-like fins
Publication No. 6) etc. have been made.

In the case shown in FIG. 8, a large number of louver plates 15 are cut and raised in a plate-like fin 11 to form an opening 16, forming a louver-like shape, and a heat exchanger tube 12 is inserted into the plate-like fin 11 and placed adjacent to each other. The front end portions 13 and rear end portions 14 of the plate-like fins 11 are closed with respect to the fluid flow direction X as shown in the figure.

In addition, in the case shown in FIG. 9, heat transfer tubes 22 are inserted into net-like fins 21 formed by braiding thin wires as shown in FIG. The front end portions 21a and the rear end portions 21b are closed with respect to the X as shown in FIG.

However, both of the devices shown in FIGS. 8 and 9 have a problem in that the fins have a complicated shape and require a large amount of man-hours and time to manufacture, resulting in an expensive product.

Therefore, the present inventors first proposed that in an ultra-thin tube heat exchanger with an inner diameter of 5.5 mφ and an outer diameter of 6 mm or less, a flow resistor was braided into a thin tube in a rather-like shape as shown in FIG. A device with improved performance was proposed (see Japanese Patent Laid-Open No. 153388/1988).

In this heat exchanger, as shown in FIG. 5, a supply header 2 and a discharge blower 3 communicate with each other via a large number of thin tubes 1 arranged in parallel on a plane, and a flow resistor 5 made of a large number of thin wires. The heat exchange portion is constructed by braiding the two in a rather knitted manner, with the weft being the weft and the thin tube 1 being the warp. and,
With such a configuration, the flow of the heating fluid or fluid to be heated passing through the outside of the thin tube 1 (indicated by arrow 4)
changes its direction due to the resistance of the flow resistor 5, and the thin tube 1
By flowing along the axial and circumferential directions of the fluid while contacting the surface of the fluid, the contact area and time of the fluid with the thin tube 1 are increased, thereby improving heat exchange efficiency.

In addition, Fig. 6 and Fig. 7 show the flow of fluid (indicated by arrow 4).
In order to reduce the resistance and improve performance, the heat exchanger tubes 1 are arranged in parallel, and the one shown in Fig.
The device shown in FIG. 7 proposes a device consisting of a plurality of stages of heat exchanger tube groups so that each heat exchanger tube group is arranged in three stages independently (see Japanese Patent Laid-Open No. 153383/1983).

[Problems to be Solved by the Invention] However, in the device proposed in JP-A-61-153388 shown in Fig. 5, the fluid flow is resisted by the installation of the flow resistor, making it difficult for the fluid to flow. The disadvantage is that the efficiency does not improve, and the device proposed in JP-A-61-153383 shown in Figures 6 and 7 has the disadvantage that the device becomes three-dimensionally large due to the multiple stages of heat transfer tubes. was there.

The present invention has been made in view of these conventional problems, and aims to solve the above problems by layering a plurality of thin tube groups in a lattice shape.

[Means for solving problems]

The present invention comprises a non-linear fluid supply header and a discharge pipe, and a plurality of thin tube groups in which a large number of thin tubes are arranged in parallel at approximately the same interval in a plane, and one tube end of the thin tube group. a heat exchanger in which one end of the tube is connected to the supply header and the other end of the tube is connected to the discharge header, and the plurality of capillary tube groups include those in which the capillary tubes are oriented in one direction and those in which the tubes intersect with the other. The thin tube groups in one direction are alternately layered to form a lattice shape, and the thin tube groups in one direction are adjacent to each other through the thin tube groups in the other direction, and the parallel pitch of the thin tubes is shifted by about 1/2 from each other. This is a heat exchanger installed.

[Effect]

Since the present invention has the above-described structure, the thin tube group formed in multiple layers in a lattice pattern has an extremely large surface area, that is, a heat transfer area, and the fluid passing through the thin tube group has a complicated flow. The heat exchange efficiency is greatly improved compared to conventional methods because the flow rate is constant and the contact time with the tubes is long, as the flow rate is constant and the flow rate is constant as the flow rate is changed while changing the path and contacting all the tubes that make up the tube group in the circumferential and axial directions. In addition, since the heat exchange part is compactly constructed with a group of thin tubes,
It becomes a compact device.

〔Example〕

The present invention will be explained below based on the drawings. Figures 1 to 4
The figure is a diagram illustrating an embodiment of the present invention.

In this embodiment, an example in which both a non-linear fluid supply header and a discharge header are formed in an L-shape will be described.

In the figure, 32 is an L-shaped fluid supply header consisting of a long side 32a, a short side 32b, and a fluid supply port 32c, and 33 is a fluid discharge header symmetrical to the supply header 32, with a long side 32b and a fluid supply port 32c. It consists of a side 33a, a short side 33b, and a fluid outlet 33c.

The supply header 32 and the discharge header 33 are assembled to form a rectangular shape as shown in FIG.

31A, 31B, and 31C are a large number of thin tubes 31 as shown in FIG.
is a group of thin tubes formed in parallel in a plane at intervals of pitch L, one tube end of each tube communicates with the short side 32b of the supply header 32, and the other tube end communicates with the short side of the discharge header 33. It communicates with 33b.

As shown in FIGS. 1 to 3, 34A and 34B are a group of thin tubes in which a large number of thin tubes 34 are formed in parallel in a plane at intervals of a pitch L2, and one tube end of each tube is connected to the supply header 3.
2, and the other pipe end is connected to the discharge header 33.
It communicates with the long side 33a of.

Further, all the thin tubes 31 are arranged in the A-A direction, and the thin tubes 34
are all arranged in the B-B direction, and the tube groups consisting of these are, for example, 348 under 31A, 31B under 34A, 34B under 31B, and 3IC under 34B.
are arranged in layers so as to form a lattice shape.

Furthermore, as shown in FIGS. 2 and 3, in the arrangement of the capillary group 31A, the capillary group 31B has a structure in which the capillary tubes 31 of 31B are 31A.
The pitch L of the thin tubes 31 is located approximately in the middle of the pitch L of the thin tubes 31 . This is also arranged in the same relational position as above in the thin tube groups 34A and 34B.

L3 indicates the pitch between the thin tubes 31 and 34 (the third
figure).

With the above configuration, the fluid flow shown by the arrow 4 in FIG. 2 is as follows:
By passing through the tubes in contact with each other in the order of Since the contact time with the thin tubes is long, the heat exchange efficiency is greatly improved compared to the conventional method, and the main part that performs heat exchange is compactly constructed with a group of thin tubes, so the device can be made smaller.

Further, in this embodiment, the supply head and the discharge header are L-shaped, but the present invention is not limited to this shape; for example, they may be semicircular or semielliptical.

It can be applied to all non-linear shapes, including half-frame shapes.

The results of an experiment conducted in this example under the following conditions are shown below.

Under the experimental conditions, the fluid is air at room temperature, the liquid inside the capillary is 80℃ hot water, and the diameter of the capillary is outer diameter D = 2 m, inner diameter = 1.8 am, as the minimum required heat transfer rate (W / m・"C) 2
000W/n?・In order to ensure the temperature at °C, the distance between the intersecting thin tubes (L3) ÷ the thin tube diameter (D) = 2.0 to 5.0 (see Figure 4), and the distance between the thin tubes in different directions must be However, the upper and lower groups of thin tubes in the same direction, for example, 31A and 31B in FIG. 3, are arranged at positions shifted by L, /2 in the left-right direction in the figure to maximize the heat transfer efficiency, which is the heat passage rate. I got the results that I could.

In addition, in the above embodiment, an example was explained in which hot water was used as the liquid in the capillary and air was used as the fluid that contacted the capillary.
It goes without saying that these can be similarly applied to exhaust gas, high-temperature gas, high-temperature fluid, refrigerant, etc., either on the cooling side or on the cooled side, depending on the equipment and purpose.

〔Effect of the invention〕

As explained above, according to the heat exchanger according to the present invention,
There is no need to attach fins that require a lot of time and money to manufacture as in the past (and there are no obstacles such as flow resistance elements that obstruct the passage of fluid, so pressure loss is small, and heat exchange efficiency is improved. It is possible to obtain a small and inexpensive heat exchanger with high performance.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an embodiment according to the present invention, Fig. 2 is a sectional view taken along line nn in Fig. 1, Fig. 3 is a partially enlarged explanatory view of Fig. 2, and Fig. 4 shows the effects of the embodiment. Figure 5 is a perspective view of a conventional example in which thin wires are braided, Figure 6 is a perspective view of a conventional example in which heat exchanger tube groups are used in two stages, upper and lower, and Figure 7 is a perspective view in which heat exchanger tube groups are used in three stages. FIG. 8 is a partial sectional view of the conventional example using louvered fins, FIG. 9(a) is a partial view of the conventional example using mesh fins, and FIG. It is an IX-IX sectional view of al. 2...Fluid supply header, 3...Fluid discharge header, 31.34... Thin tube, 31A,
31B, 31C, 34A, 34B...tubule group,
L,,L,...Pitch. Patent Applicant Kawasaki Steel Corporation Agent Patent Attorney Tetsuya Mori Agent Patent Attorney Yoshiaki Naito Agent Patent Attorney Shimizu Positive heat transfer rate (W/m”・C)

Claims (1)

[Claims] It comprises a non-linear fluid supply header and a discharge header, and a plurality of thin tube groups formed by paralleling a large number of thin tubes at approximately the same intervals in a plane, and one tube end of the thin tube group is connected to the supply header. The heat exchanger is configured such that the tubes communicate with each other and the other tube end is connected to the discharge header, and the plurality of thin tube groups have thin tubes oriented in one direction and those in the other direction that intersect therewith. The thin tube groups in one direction that are alternately layered to form a lattice shape and are adjacent to each other via the thin tube groups in the other direction are arranged such that the parallel pitch of the thin tubes is shifted by about 1/2 from each other. A heat exchanger featuring: